When there is a separate comment that you want to say, but it isn't necessarily related or necessary to the block of text.
P.S. means Post Script or after writing(Post=after,Script=writing). P.S.S would probaly be just some over use of it.
PPS stands for "Post Post Script". Just as PS stands for "Post Script", PPS stands for "Post Post Script", PPPS would stand for "Post Post Post Script" etc. A post script is any text written below the signature on a letter. If you forget to write something in the letter, you would put the in the PS, is you forget to write some in the PS would would write a PPS, and so on.
P.S. also means 'Post Script'
In a letter, you would 'add the ps' after (below) signing the letter. A Post script can be added by using the initials like so:P.s: Or, you may even add a Post post script by using THESE initials:P.p.s: I hope this posting of Post script and Post post script usage is of some use to you.
P.S. at the end of a letter stands for Post Script. Post=after and script=letter. After Letter message. And P.P.S. = post, post script. They are both for if you forgot to write something in the letter, and want to add it in.
post script was developed by Adobe systems.
It would be P.P.S. because P.A. stands for "post script". So P.P.S. stands for "post-post script".
PS.
Short for "post script" meaning after writing. Some thing that is added after the main text.
Post post script most common.
Post Script is just another meaning of P.S when written at the end of a letter to add an additional piece of information.
The post script is after a letter. It also Means P.S.